1. Field of the Invention
The present invention relates to an apparatus for securely retaining absorbent sheets or pads for use in collecting and disposing of pet wastes. In particular, the present invention relates to a device for securely retaining a disposable, absorbent sheet in a leakproof reservoir.
2. Description of Related Art
Many devices have been proposed to aid in housebreaking of pets and, in particular, dogs. When indoors, it is desirable for the pets to urinate and defecate at a single, predetermined location. Several methods and devices have been proposed to provide a disposable waste collector at the predetermined location.
Traditionally, newspapers have been laid on the floor for a dog's use. Although newspapers are absorbent, unrestrained newspapers can easily scatter when exposed to drafts or can be scattered or torn by a playful or destructive animal. Another drawback of newspapers is that they readily leak through to the floor surface upon which they are laid.
To eliminate the leaking problem, several absorbent pads have been proposed. U.S. Pat. Nos. 3,626,899; 4,800,677; and 5,630,376 all describe collection pads including at least one layer of absorbent material and a backing layer of material that is impervious to fluid so as to preclude urine from leaking through the pad to the surface of the floor. However, although these devices can preclude fluid leakage, when unrestrained, they, too, can be readily scattered or torn by drafts or pets.
U.S. Pat. No. 4,949,673 proposes a chamber pot for pets in which a water-absorptive sheet can be laid over a soil bed surrounded by peripheral walls. The water-absorptive sheet is drawn out of a roll, cut and laid on the soil bed. A presser frame hinged to the soil bed is then lowered and engaged with a locking device. The bottom face of the presser frame presses and clamps the periphery of the sheet placed on the soil bed. However, the chamber pot requires a complicated structure in order to retain the absorptive sheet in a tray. This can lead to higher costs and a complicated manufacturing process. Further, because there is only a single line of peripheral contact between the presser frame and the periphery of the absorptive sheet, a pet can readily dislodge the absorptive sheet from the frame.
U.S. Pat. No. 4,715,320 relates to a sanitary receptacle for animal waste that is formed of three concentric hoops and a sheet of thin flexible material, such as newspaper. The newspaper is spread over the inner hoop and then captured in an annular space between the inner and center hoops when the center hoop is placed over the inner hoop. This assembly is then inverted and the outer hoop is pushed over the newspaper and the center hoop, thereby capturing the newspaper between the center and outer hoops. However, in this device nothing is disposed between the newspaper and the floor, so animal waste can leak through to the floor surface. Further, assembly of the device is complex, requiring multiple steps to secure the newspaper within the three hoops.